Gaithersburg began as a small settlement at the juncture between two trails, now Frederick Avenue and Diamond Avenue. The arrival of the Baltimore and Ohio Railroad in 1873 sparked a business and agricultural expansion that made the Gaither settlement the commercial center for upper Montgomery County, and it was incorporated as the town of Gaithersburg in 1878. A second major expansion occurred in the 1960's, when the Atomic Energy Commission headquarters (now the Department of Energy) and the National Institute for Standards and Technology relocated to the vicinity, spurring residential and commercial growth that continues to this day.With a population of nearly 70,000, Gaithersburg is now one of the largest cities in Maryland. It is a major international location for high technology companies, and boasts award-winning schools, neighborhoods and commercial developments. Its respect for its heritage, demonstrated by the revitalization efforts in the Olde Towne residential and commercial district, coupled with thoughtful planning for new communities and a commitment to cultural and recreational activities, has earned the City national acclaim.